University of Southampton: New Study Aims to Uncover How Marine Organisms Aid in Carbon Sequestration in the Ocean
An international team of scientists, led by researchers at the University of Southampton, National Oceanography Centre (NOC), and Heriot-Watt University, are studying the role marine organisms play in storing carbon in the ocean.
A combination of field research and cutting-edge autonomous tech will provide rare in situ observations across a whole seasonal cycle – with intense sampling across the most biologically active seasons.
Scientists know that marine organisms play a critical role in storing carbon in the ocean that might otherwise remain in the atmosphere.
However, recent evidence suggests that climate models are not fully accounting for the impact of potential changes in biological processes. This could hinder predictions of the ocean’s role in future carbon storage at a critical time.
The BIO-Carbon programme , funded by the Natural Environment Research Council (NERC) , will help deliver the understanding necessary to make robust predictions for how oceanic carbon storage may alter under climate change.
Scientists have already completed the first of two expeditions, this time onboard NOC’s world-leading research vessel the RRS Discovery in the North Atlantic, south of Iceland.
Addressing critical climate challenges
The fieldwork and programme seek to address three critical challenges.
Led by Professor Mark Moore, from the University of Southampton, one project is exploring primary production, the process by which carbon is removed from the surface of the ocean and transformed into organic matter.
Primary production supports virtually all life in the sea. By combining experiments conducted on board RRS Discovery with observations made by a fleet of robots and drifting floats throughout the year, Mark and his team are examining the relative importance of the availability of light and nutrients, as well as consumption by larger organisms, in controlling this key process.
Professor Moore says: “We know that upper ocean productivity is a critical first stage in the biological storage of carbon in the ocean, but we still lack the comprehensive year-round measurements which will enable us to really understand how these processes are controlled. The combination of multiple cruises with new robotic platforms represents an exciting opportunity to close this observation gap.”
Another project led by Professor Stephanie Henson from NOC is gaining a better understanding of how climate change will affect the rate at which the marine ecosystem releases carbon dioxide by using organic carbon as a source of energy, in a process called respiration.
In addition to using advanced cameras and robots to examine how carbon in dead organisms is consumed as it sinks, Stephanie and her team have deployed a new piece of equipment that acts like a freely drifting mini laboratory, which is quantifying the rate at which organic material is being respired in situ.
Fieldwork led by Professor Alex Poulton from The Lyell Centre at Heriot-Watt University is gaining a better understanding of how specific organisms, called coccolithophores, which build intricate ‘shells’ through a process called calcification, can affect the ability of seawater to absorb carbon dioxide from the atmosphere.
To do this, Alex and the team have undertaken novel measurements and experiments at sea, using an innovative suite of new sensors on the ship, on ocean robots and on satellites to look at how viral infection and consumption by small animals influence coccolithophore “blooms”, often referred to as “white waters” or “white tides” by sailors. During the Spring expedition, the team encountered a massive bloom of coccolithophores in the far northeast of the Atlantic. The current bloom in the Iceland Basin to the South of Iceland is roughly the size of Scotland.
Cutting-edge ocean robots
Additionally, a joint BIO-Carbon-FMRI mission has seen the use of two autonomous vehicles, Autosub Long Range (ALR) – better known as Boaty McBoatface. Both are equipped with a suite of cutting-edge sensors to analyse the biology and chemistry of the ocean.
The mission marked the first country to country deployment for an ALR, with ALR 4 crossing the Iceland Basin from Reykjavik to Harris, in the Scottish Outer Hebrides. This is also the first time NOC have deployed two ALRs simultaneously for one mission, pushing the boundaries of robotic ocean exploration.
Future fieldwork
The second BIO-Carbon expedition will take place this autumn onboard the NOC-operated RRS James Cook. The researchers will see the retrieval of the robotic platforms deployed on the spring expedition and a continuation of groundbreaking BIO-Carbon fieldwork.